title: Mycoplasma, bacterial vaginosis-associated bacteria BVAB3, race, and risk of preterm birth in a high-risk cohort.
abstract: OBJECTIVE
  Genital tract infection accounts for approximately 25-40% of all preterm births. We sought to assess the relationship between preterm birth and selected vaginal bacterial taxa associated with preterm birth either directly or through their association with bacterial vaginosis (BV).
  
  
  METHODS
  Vaginal fluid for Gram stain was collected between 17 and 22 weeks' gestation as part of a randomized trial of ultrasound-indicated cerclage for preterm birth prevention in women at high risk for recurrent spontaneous preterm birth. Bacterial deoxyribonucleic acid was extracted from the Gram stain slides and analyzed using quantitative polymerase chain reaction.
  
  
  RESULTS
  Among the 499 participants, Mycoplasma was positively correlated with increased risk of preterm (risk ratio [RR], 1.83; 95% confidence interval [CI], 1.52-2.22) as was Mobiluncus (RR, 1.36; 95% CI, 1.07-1.73) and Atopobium (RR, 1.44; 95% CI, 1.1-1.87). However, there were strong interactions between the race/ethnic group and the presence of these and other individual taxa on risk of preterm birth. By contrast, bacterial vaginosis-associated bacteria (BVAB)-3 was consistently associated with a reduction in the risk of preterm birth for all racial/ethnic groups (0.55; 95% CI, 0.39-0.78).
  
  
  CONCLUSIONS
  BV is characterized by a reduction of Lactobacillus, and lactic acid-producing bacteria and the presence of Mobiluncus; we found these factors and the presence of Mycoplasma to be associated with an increased risk of preterm birth. By contrast, the presence of a recently identified organism sufficient to cause BV, BVAB3, decreased the risk of preterm birth. These findings give insight into why treating BV has mixed impact on risk of preterm birth.
authors.affiliation: Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI. Electronic address: bfoxman@umich.edu.
authors.forename: Betsy
authors.initials: B
authors.lastname: Foxman
authors.affiliation: Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI.
authors.forename: Ai
authors.initials: A
authors.lastname: Wen
authors.affiliation: Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI.
authors.forename: Usha
authors.initials: U
authors.lastname: Srinivasan
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Michigan Medical School, Ann Arbor, MI.
authors.forename: Deborah
authors.initials: D
authors.lastname: Goldberg
authors.affiliation: Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI.
authors.forename: Carl F
authors.initials: CF
authors.lastname: Marrs
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, The University of Alabama at Birmingham, Birmingham, AL.
authors.forename: John
authors.initials: J
authors.lastname: Owen
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of California at Irvine School of Medicine, Irvine, CA.
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Wing
authors.affiliation: Department of Family Medicine and Public Health Sciences, School of Medicine, Wayne State University, Detroit, MI.
authors.forename: Dawn
authors.initials: D
authors.lastname: Misra
mesh_terms: D000328:Adult; D001741:Black or African American; D004269:DNA, Bacterial / Q000302:isolation & purification; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D007231:Infant, Newborn; D017904:Mobiluncus / Q000235:genetics / Q000302:isolation & purification; D009174:Mycoplasma / Q000235:genetics / Q000302:isolation & purification*; D007752:Obstetric Labor, Premature / Q000209:etiology* / Q000382:microbiology / Q000517:prevention & control; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis* / Q000382:microbiology; D047928:Premature Birth / Q000209:etiology* / Q000382:microbiology / Q000517:prevention & control; D012307:Risk Factors; D014621:Vagina / Q000382:microbiology; D016585:Vaginosis, Bacterial / Q000150:complications / Q000175:diagnosis* / Q000382:microbiology; D044465:White People
chemical_list: D004269:DNA, Bacterial
keywords: bacterial vaginosis; genital tract infection; preterm birth; vaginal bacterial taxa